Hyperspectral Imaging

Hyperspectral Imaging 

A 21st Century Tool for Resource Management

A New Way to Look at the World

A stretch of desert, an expanse of sea, a blanket of forest, a checkerboard of crops. Familiar vistas: scenic, but nothing out of the ordinary. Unless you know how to look.

With the right tool — a Northrop Grumman hyperspectral imager — detailed pictures emerge: a vehicle hidden by camouflage, an area teeming with fish food, trees growing at different rates, fertile land under-utilized.

By seeing what cannot be seen by the human eye, a hyperspectral imaging system gives resource managers — front-line commanders, farmers, urban planners, foresters, environmental analysts — a powerful tool to help classify features, measure productivity/yield and identify trends.

Bringing to Light

All objects — soil, water, trees, vegetation, structures, metals, paints, fabrics — create a unique spectral fingerprint. A sensor determines these fingerprints by measuring reflected light, most of which registers in wavelengths, or bands, invisible to humans.

Northrop Grumman's state-of-the-art hyperspectral imaging systems operate across up to 220 wavelengths to paint precise portraits of this hidden world. Where a standard sensor with fewer than 10 bands is capable only of differentiating between gross classes of vegetation, a hyperspectral imager can discriminate a maple from an oak, wheat from alfalfa, and is sensitive enough to separate healthy from unhealthy growth.

Images in Action

These finely tuned sensors are coupled with powerful processing algorithms to provide a tool that has as many applications as there are spectral bands. With hyperspectral imaging, a camouflaged missile is transformed into a landmark, a fleet sets a course for fertile fishing beds, tree growth patterns lead to harvesting efficiencies, a farmer rotates crops.

At Any Altitude

Hyperion, NASA's first hyperspectral imager to become operational on-orbit, was launched in November, 2000. Built and delivered by Northrop Grumman, the 220-band instrument is setting the standard for orbiting imagers, providing a more than thirty-fold increase over multispectral capability now aloft. While spaceborne hyperspectral sensors provide pre-planned overflights for large-scale sensing operations, instruments flown aboard fixed wing aircraft offer flexible scheduling for local surveys. Northrop Grumman currently performs airborne data collection with the TRWIS III with image spatial resolutions spanning from less than 1 meter to more than 11 meters, with spectral coverage from 380 to 2450 nm. Spectral resolution is 5.25 nm in the visible/near infrared (380 - 1000 nm) and 6.25 in the short wave infrared (1000 - 2450 nm). Data is digitized to 12 bits, offering superb dynamic range in the video data.

Sensors and Instruments

Sensors and InstrumentsWe have decades of experience as both an instrument developer and a systems prime contractor integrating highly reliable sensors. Northrop Grumman's sensor and instrument technologies are considered "centers of excellence." The team overseeing these technologies designs, builds and operates a number of payloads in a select set of areas: precision radiometry; state-of-the-art hyperspectral imagers; and passive millimeter wave cameras. This team also conducts sensor modeling, design, engineering, analysis, test and integration.

As a system prime, we also integrate the best sensors and instruments built by our industry partners. These systems have an outstanding track record with NASA, and they've performed critical service to scientists in understanding the Earth's climate and determining the influence of clouds on global warming. In 2003 NASA gave us its prestigious Public Service Group Award for our design, fabrication, assembly, test, calibration and delivery of six CERES flight-qualified instruments. CERES (Clouds and the Earth's Radiant Energy System) is a precision three-channel broadband scanning radiometer - and the on-orbit radiometric performance was declared "excellent" by the CERES science team.

Our performance as a systems integrator led to our winning a $2.9 billion prime contract to build NPOESS (National Polar-orbiting Operational Environmental Satellite System), the nation's next-generation meteorological satellite system. NPOESS merges existing military and civilian weather polar-orbiting satellite programs into a single, national system that will provide remote-sensing capability for civil, military and scientific purposes.

Among the technologies we're pioneering for NPOESS are Sensor Modeling and Simulation Testbeds, such as our Environmental product Verification and Remote Sensing Testbed (EVEREST). EVEREST is being built to support mission utility analyses and to define requirements, predict performance and independently verify and validate calibrations and algorithm performance.

Building upon Northrop Grumman's substantial experience in sensors, we'll continue to develop new technologies - expanding the range of the sensors we build, improving our design and integration processes and strengthening our capabilities in phenomenology and data exploitation.